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1.
We explored patterns of plant species richness at different spatialscales in 14 habitats in a Swedish rural landscape. Effects of physicalconditions, and relationships between species richness and management historyreaching back to the 17th century were examined, using old cadastralmaps andaerial photographs. The most species-rich habitats were dry open semi-naturalgrasslands, midfield islets and road verges. Alpha diversity (species richnesswithin sites) was highest in habitats on dry substrates (excluding bedrock withsparse pines) and beta diversity (species richness among sites) was highest inmoist to wet habitats. Alpha and beta components of species richness tended tobe inversely related among habitats with similar species richness. Managementhistory influenced diversity patterns. Areas managed as grasslands in the17th and 18th century harboured more species than areasoutside the villages. We also found significant relationships between speciesrichness and soil type. Silt proved to be the most species-rich topsoil(10–20 cm) in addition to thin soils top of on green- orlimestone bedrock. The variation in species richness due to local relief orform of thesite also showed significant relationships, where flat surfaces had the highestnumber of species. In contrast, no significant relationship was found betweenspecies richness and aspect. Our study suggests that present-day diversitypatterns are much influenced by management history, and that small habitat,e.g., road verges and midfield islets, are important for maintaining speciesrichness.This revised version was published online in May 2005 with corrections to the Cover Date. 相似文献
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Landscape Ecology - Theory predicts that species diversity of isolated habitat patches depends on patch size and isolation. However, there are few previous studies of how patch size and isolation... 相似文献
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Determining how suburbanization shapes tree-species composition and diversity is vital in Canadian and most nations’ cities, as suburban and peri-urban areas continue to grow faster than any other region. These areas, characterized by various land types and uses, represent differences in management and governance, jurisdiction, planting practices and species selection, and professional and political agendas. Such complexities emphasize the importance of exploring the influence of various environmental and location attributes of suburban neighbourhoods. Using hierarchical cluster analysis to classify urban forest species assemblages, we found that location attributes such as land type, development decade, and geography are influential on species composition and diversity − but only to an extent. We found that street-tree assemblages were classified more distinctly than remnant woodlands, which were in turn more distinct than tree communities found on residential properties. Residential land types had a high degree of species heterogeneity, highlighting the importance of not only considering the location attributes chosen for this study, but also including socioeconomic and cultural variables in future ecological classification schemes. Identifying drivers of species composition and diversity is useful for developing and implementing forest management strategies for urban and peri-urban areas, as different species assemblages give rise to different challenges and management opportunities, as well as varying quantities of ecosystem services, values, and benefits. 相似文献
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To test the effects of connectivity on fish diversity in isolated reef patches we deployed pairs of artificial reefs (AR)
at constant distances (12 and 25 m) from a large continuous reef and added series of small ARs to half of them. These small
reefs served as stepping-stones to increase fish movement between the large ARs and the continuous reef. Species gain and
loss curves were compared to obtain deeper understanding of the underlying mechanisms in relation to the theory of island
biogeography. We found that AR without stepping-stones maintained up to 57-fold more individuals than ARs with stepping-stones
during mass recruitment events that were dominated by the family Apogonidae. However, in-between these mass recruitment events
the overall impact of the stepping-stones on richness and abundance was small. By contrast, increasing distance from the continuous
reef from 12 to 25 m increased fish richness, although this was confounded with time since AR deployment. Increase in richness
with distance was predominantly caused by elevated species gain. Our results suggest that fish assemblages respond in distinct
ways to two types of isolation: (1) Increased richness with distance from a continuous reef, and (2) increased fluctuation
in abundance with decreased connectivity. The latter may be the outcome of accumulation and then abrupt emigrations of fishes
from isolated reefs. This study confirms that the spatial setting of reef patches in relation to larger or continuous reefs
alters fish assemblages, which may be important for planning AR deployments that maximizes diversity. 相似文献
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Small mammals in a mosaic of forest remnants and anthropogenic habitats—evaluating matrix quality in an Atlantic forest landscape 总被引:1,自引:0,他引:1
The matrix of altered habitats that surrounds remnants in human dominated landscapes has been considered homogeneous and inhospitable.
Recent studies, however, have shown the crucial role of the matrix in maintaining diversity in fragmented landscapes, acting
as a mosaic of units with varying permeability to different species. Inclusion of matrix quality parameters is especially
urgent in managing fragmented landscapes in the tropics where agriculture frontiers are still expanding. Using standardized
surveys in 23 sites in an Atlantic forest landscape, we evaluated matrix use by small mammals, the most diverse ecological
group of mammals in the Neotropics, and tested the hypothesis that endemic species are the most affected by the conversion
of original forest into anthropogenic habitats. By comparing species distribution among forest remnants and the predominant
adjacent habitats (native vegetation in initial stages of regeneration, eucalyptus plantations, areas of agriculture and rural
areas with buildings), we found a strong dissimilarity in small mammal assemblages between native vegetation (including initial
stages) and anthropogenic habitats, with only two species being able to use all habitats. Endemic small mammals tended to
occupy native vegetation, whereas invading species from other countries or open biomes tended to occupy areas of non-native
vegetation. Our results highlight that future destruction of native vegetation will favor invading or generalist species which
could dominate highly disturbed landscapes, and that some matrix habitats, such as regenerating native vegetation, should
be managed to increase connectivity among populations of endemic species. 相似文献
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Diego R. Macedo Robert M. Hughes Raphael Ligeiro Wander R. Ferreira Miriam A. Castro Nara T. Junqueira Deborah R. Oliveira Kele R. Firmiano Philip R. Kaufmann Paulo S. Pompeu Marcos Callisto 《Landscape Ecology》2014,29(6):1001-1016
Landscape and site-scale data analyses aid the interpretation of biological data and thereby help us develop more cost-effective natural resource management strategies. Our study focused on environmental influences on stream assemblages and we evaluated how three classes of environmental variables (geophysical landscape, land use and cover, and site habitat), influence fish and macroinvertebrate assemblage richness in the Brazilian Cerrado biome. We analyzed our data through use of multiple linear regression (MLR) models using the three classes of predictor variables alone and in combination. The four MLR models explained dissimilar amounts of benthic macroinvertebrate taxa richness (geophysical landscape R 2 ≈ 35 %, land use and cover R 2 ≈ 28 %, site habitat R 2 ≈ 36 %, and combined R 2 ≈ 51 %). For fish assemblages, geophysical landscape, land use and cover, site habitat, and combined models explained R 2 ≈ 28 %, R 2 ≈ 10 %, R 2 ≈ 31 %, and R 2 ≈ 47 % of the variability in fish species richness, respectively. We conclude that (1) environmental variables differed in the degree to which they explain assemblage richness, (2) the amounts of variance in assemblage richness explained by geophysical landscape and site habitat were similar, (3) the variables explained more variability in macroinvertebrate taxa richness than in fish species richness, and (4) all three classes of environmental variables studied were useful for explaining assemblage richness in Cerrado headwater streams. These results help us to understand the drivers of assemblage patterns at regional scales in tropical areas. 相似文献
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Traditional agricultural mosaic landscapes are likely to undergo dramatic changes through either intensification or abandonment
of land use. Both developmental trends may negatively affect the vascular plant species richness of such landscapes. Therefore,
sustainable land-use systems need to be developed to maintain and re-establish species richness at various spatial scales.
To evaluate the sustainability of specific land-use systems, we need approaches for the effective assessment of the present
species richness and models that can predict the effects on species richness as realistically as possible. In this context,
we present a methodology to estimate and predict vascular plant species richness at the local and the regional scale. In our
approach, the major determinants of vascular plant species richness within the study area are taken into consideration: These
are according to Duelli's mosaic concept the number of habitat types and of habitat patches within area units. Furthermore,
it is based on the relative frequencies of species within habitat types. Our approach comprises six steps: (i) the determination
of present habitat patterns within an observation area, (ii) the creation of a land-use scenario with simulated habitat patterns,
(iii) the determination of species frequencies within habitat types of this area, (iv) a grouping of habitat-specific species,
(v) the estimation of the probabilities for all species (or habitat specialists) to occur, either in stepwise, exponentially
enlarged landscape tracts (local scale), or in the entire observation area (regional scale), and (vi) the validation of the
estimated species numbers. The approach will be exemplified using data from the municipal district of Erda, Lahn-Dill Highlands,
Germany. The current species numbers to be expected on the basis of probability calculations were compared with those recorded
on the basis of extensive field work. This comparison shows that, on the basis of our simple calculations, the current local
plant species richness can be predicted well, with a slight underestimation.
This revised version was published online in May 2005 with corrections to the Cover Date.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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V. H. Dale L. K. Mann R. J. Olson D. W. Johnson K. C. Dearstone 《Landscape Ecology》1990,4(4):211-224
Forest structure and composition influence patterns of insect outbreaks and can be explained on the Walker Branch watershed by past land use (timber harvest and agriculture), soils, aspect, and slope. In particular, pine bark beetles caused large losses of pine on sites that had been used for agriculture, on Fullerton silt loam soils, and on north-to-northeast and east-to-southeast exposures. Hickory bark beetles had a high impact on hickory biomass on Bodine soil areas that were forested in 1935 and sloped greater than 11%. Thus, prior land use can have an indirect effect on future disturbances.Because forest disturbances can affect nutrient distribution, land use can also indirectly affect nutrient availability. For example, locations of hickory bark beetle outbreaks experience a large flux of calcium from dead wood to soil because hickory accumulates large amounts of calcium in woody tissue. The research demonstrates a link between past land use, insect outbreaks, and calcium cycling. 相似文献
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Endenburg Sarah Mitchell Greg W. Kirby Patrick Fahrig Lenore Pasher Jon Wilson Scott 《Landscape Ecology》2019,34(10):2385-2399
Landscape Ecology - Agricultural expansion is a principal driver of biodiversity loss, but the impacts on community assembly in agro-ecosystems are less clear, especially across regional scales at... 相似文献
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Elizabeth R. Hobbs 《Landscape Ecology》1988,1(3):141-152
The vascular plant species richness of upland urban forest patches in St. Paul and Minneapolis, Minnesota, was found to be positively related to their size. There was no significant relationship between species richness and the distance of these patches to other patches. Mowing and trampling reduced species richness of patches, whereas planting increased richness. Landscape richness can be maintained at a relatively high level by leaving even small unmown forested patches within a more disturbed matrix. However, maximizing landscape diversity would require leaving large forest stands unmown. It is suggested that cultivation be deliberately used as a mechanism for increasing native species richness in urban forests. 相似文献
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Ecological theory predicts a positive influence of local-, landscape-, and regional-scale spatial environmental heterogeneity
on local species richness. Therefore, knowing how heterogeneity measured at a variety of scales relates to local species richness
has important implications for conservation of biological diversity. We took a statistical modeling approach to determine
which metrics of heterogeneity measured at which scales were useful predictors of local species richness, and whether the
heterogeneity-local richness relationship was always positive. Local plant species richness data came from 400-m2 vegetation plots in North and South Carolina, USA. At each of four scales from within plots to across regions, we used either
GIS or field data to calculate measures of heterogeneity from abiotic environmental variables, vegetation productivity data,
and land cover classifications. Among all predictors at all scales, we found that no measure of heterogeneity was a better
predictor of local richness than mean pH within plots. However, at scales larger than within plots, measures of heterogeneity
were correlated most strongly with local richness, and each of the three classes of variables we used had a distinct scale
at which it performed better than the others. These results highlight the fact that ecological processes occurring across
multiple scales influence local species richness differently. In addition, relationships between heterogeneity and richness
were usually, though not always, positive, underscoring the importance of processes that occur at a variety of scales to local
biodiversity conservation and management. 相似文献
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Abundance and richness are the two fundamental components of speciesdiversity. They represent two distinct types of variables of which the formerisadditive when aggregated across scales while the latter is nonadditive. Thisstudy investigated the changes in the spatial patterns of abundance andrichnessof tree species across multiple scales in a tropical rain forest of Malaysiaandtheir variations in different regions of the study area. The results showedthatfrom fine to coarse scales abundance had a gradual and systematic change inpattern, whereas the change in richness was much less predictable and ahotspot in richness at one scale may become acoldspot at another. The study also demonstrated that differentmeasures of diversity variation (e.g., variance and coefficient of variation)can result in different or even contradictory results which further complicatedthe interpretation of diversity patterns. Because of scale effect the commonlyused measure of species diversity in terms of unit area (e.g.,species/m2) is misleading and of little use in comparing speciesdiversitybetween different ecosystems. Extra care must be taken if management andconservation of species diversity have to be based on information gathered at asingle scale.This revised version was published online in May 2005 with corrections to the Cover Date. 相似文献
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Mantero Giulia Morresi Donato Marzano Raffaella Motta Renzo Mladenoff David J. Garbarino Matteo 《Landscape Ecology》2020,35(12):2723-2744
Landscape Ecology - Since the nineteenth century, rural areas have experienced progressive abandonment mostly due to socioeconomic changes, with direct and indirect effects on forest disturbance... 相似文献
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Effects of landscape structure and forest reserve location on old-growth forest bird species in Northern Finland 总被引:4,自引:0,他引:4
Brotons Lluís Mönkkönen Mikko Huhta Esa Nikula Ari Rajasärkkä Ari 《Landscape Ecology》2003,18(4):377-393
Old-growth forest birds in Fennoscandia have sharply declined in numbers during the last decades apparently due to commercial
forest harvesting and fragmentation of old-growth forests. Conservation measures have led to the establishment of a forest
reserve network to assure the persistence of forest birds at a regional scale. However, little is known about the effects
of landscape structure within and around the reserves on the distribution of old-growth forest birds. We used a hierarchical
approach to address the questions of how landscape structure and composition within forest reserves, landscape composition
of surrounding areas and reserve location affect the abundance of resident, old-growth forest birds in the Northern Finnish
forest reserve network. The positive role of particular landscape features on bird distribution indicates that both the proportion
of old-growth forests and the structure of boreal landscape mosaic has an important role in determining the distribution of
these birds. The landscape composition surrounding the reserves proved to be only a weak predictor in species distribution
models, which argues against the primary role of the surrounding matrix in determining species distribution within forest
reserves. Reserves located near the Russian border showed a higher abundance of old-growth birds than more western ones. Once
east-west gradients in overall landscape composition had been accounted for, however, reserves did not differ significantly
in the number of species present. These results suggest that landscape gradients, rather than ecological processes such as
the presence of source areas located along the border with Russia, are the main determinant of the distribution of old-growth
forest birds in the Finnish reserve network. We propose that to enhance regional persistence of old-growth forest birds, conservation
efforts should be primarily directed towards the protection and enhancement of forest habitat quality and natural heterogeneity
of landscapes within targeted areas.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Bitters Matthew E. Hicks Andrew Holtz Spencer Acruri Paulina Wilson Robert Resasco Julian Davies Kendi F. 《Landscape Ecology》2022,37(6):1483-1495
Landscape Ecology - Earth's forests are fragmented. Species' long-term persistence depends on their conservation in fragmented landscapes with remnants embedded in a matrix of human land... 相似文献
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Jenica M. Allen Thomas J. Leininger James D. Hurd Jr. Daniel L. Civco Alan E. Gelfand John A. Silander Jr. 《Landscape Ecology》2013,28(9):1671-1686
Woody invasive plants are an increasing component of the New England flora. Their success and geographic spread are mediated in part by landscape characteristics. We tested whether woody invasive plant richness was higher in landscapes with many forest edges relative to other forest types and explained land use/land cover and forest fragmentation patterns using socioeconomic and physical variables. Our models demonstrated that woody invasive plant richness was higher in landscapes with more edge forest relative to patch, perforated, and especially core forest types. Using spatially-explicit, hierarchical Bayesian, compositional data models we showed that infrastructure and physical factors, including road length and elevation range, and time-lagged socioeconomic factors, primarily population, help to explain development and forest fragmentation patterns. Our social–ecological approach identified landscape patterns driven by human development and linked them to increased woody plant invasions. Identifying these landscape patterns will aid ongoing efforts to use current distribution patterns to better predict where invasive species may occur in unsampled regions under current and future conditions. 相似文献